Mushroom poisoning (also known as mycetism) refers to harmful effects from ingestion of toxic substances present in a mushroom. These symptoms can vary from slight gastrointestinal discomfort to death. The toxins present are secondary metabolites produced in specific biochemical pathways in the fungal cells. Mushroom poisoning is usually the result of ingestion of wild mushrooms after misidentification of a toxic mushroom as an edible species. The most common reason for this misidentification is close resemblance in terms of colour and general morphology of the toxic mushrooms species with edible species. Even very experienced wild mushroom gatherers are upon rare occasion poisoned by eating toxic species, despite being well aware of the risks, through carelessness.
To prevent mushroom poisoning, mushroom gatherers need to be very familiar with the mushrooms they intend to collect as well as with any similar-looking toxic species. In addition, edibility of mushrooms may depend on methods of preparation for cooking. Collectors also need to be well aware that edibility or toxicity of some species varies with geographic location.
Poisonous mushrooms contain a variety of different toxins that can differ markedly in toxicity. Symptoms of mushroom poisoning may vary from gastric upset to life-threatening organ failure resulting in death. Serious symptoms do not always occur immediately after eating; often not until the toxin attacks the kidney or liver, sometimes days or weeks later.
The most common consequence of mushroom poisoning is simply gastrointestinal upset. Most "poisonous" mushrooms contain gastrointestinal irritants which cause vomiting and diarrhea (sometimes requiring hospitalization), but usually no long-term damage. However, there are a number of recognized mushroom toxins with specific, and sometimes deadly, effects:
- Alpha-amanitin (deadly: causes liver damage 1–3 days after ingestion)–principal toxin in genus Amanita.
- Phallotoxin (causes gastrointestinal upset)–also found in poisonous Amanitas
- Orellanine (deadly: causes kidney failure within 3 weeks after ingestion)–principal toxin in genus Cortinarius.
- Muscarine (sometimes deadly: can cause respiratory failure)–found in genus Omphalotus.
- Gyromitrin (deadly: causes neurotoxicity, gastrointestinal upset, and destruction of blood cells)–principal toxin in genus Gyromitra.
- Coprine (causes illness when consumed with alcohol)–principal toxin in genus Coprinus.
- Ibotenic acid and muscimol (hallucinogenic)–principal toxin in A. muscaria, A. pantherina, and A. gemmata.
- Psilocybin and psilocin (hallucinogenic)–principal 'toxin' in genus Psilocybe.
- Arabitol (causes gastrointestinal irritation in some people).
- Bolesatine a toxin found in Boletus satanas
- Ergotamine (deadly: affects the vascular system and can lead to loss of limbs and death): An alkaloid found in genus Claviceps.
Symptoms of mushroom poisoning vary depending on the toxins involved.
- Alpha-amanitin: For 6–12 hours, there are no symptoms. This is followed by a period of gastrointestinal upset (vomiting and profuse, watery diarrhea). This stage is caused primarily by the phallotoxins and typically lasts 24 hours. At the end of this second stage is when severe liver damage begins. The damage may continue for another 2–3 days. Kidney damage can also occur. Some patients will require a liver transplant. Amatoxins are found in some mushrooms in the genus Amanita, but are also found in some species of Galerina and Lepiota. Overall, mortality is between 10 and 15 percent. Recently, Silybum marianum or blessed milk thistle has been shown to protect the liver from amanita toxins and promote regrowth of damaged cells, including a study in which 60 patients exposed to death cap poison were given 20 mg/kg of milk thistle seeds per day within 48 hours of consuming the deadly mushrooms. None of the patients died.
- Orellanine: This toxin causes no symptoms for 3–20 days after ingestion. Typically around day 11, the process of kidney failure begins, and is usually symptomatic by day 20. These symptoms can include pain in the area of the kidneys, thirst, vomiting, headache, and fatigue. A few species in the very large genus Cortinarius contain this toxin. People who have eaten mushrooms containing orellanine may experience early symptoms as well, because the mushrooms often contain other toxins in addition to orellanine. A related toxin that causes similar symptoms but within 3–6 days has been isolated from Amanita smithiana and some other related toxic Amanitas.
- Muscarine: Muscarine stimulates the muscarinic receptors of the nerves and muscles. Symptoms include sweating, salivation, tears, blurred vision, palpitations, and, in high doses, respiratory failure. Muscarine is found in mushrooms of the genus Omphalotus, notably the Jack o' Lantern mushrooms. It is also found in A. muscaria, although it is now known that the main effect of this mushroom is caused by ibotenic acid. Muscarine can also be found in some Inocybe species and Clitocybe species, particularly Clitocybe dealbata, and some red-pored Boletes.
- Gyromitrin: Stomach acids convert gyromitrin to monomethylhydrazine (MMH), a compound employed in rocket fuel. It affects multiple body systems. It blocks the important neurotransmitter GABA, leading to stupor, delirium, muscle cramps, loss of coordination, tremors, and/or seizures. It causes severe gastrointestinal irritation, leading to vomiting and diarrhea. In some cases, liver failure has been reported. It can also cause red blood cells to break down, leading to jaundice, kidney failure, and signs of anemia. It is found in mushrooms of the genus Gyromitra. A gyromitrin-like compound has also been identified in mushrooms of the genus Verpa.
- Coprine: Coprine is metabolized to a chemical that resembles disulfiram. It inhibits aldehyde dehydrogenase (ALDH), which generally causes no harm, unless the person has alcohol in their bloodstream while ALDH is inhibited. This can happen if alcohol is ingested shortly before or up to a few days after eating the mushrooms. In that case the alcohol cannot be completely metabolized, and the person will experience flushed skin, vomiting, headache, dizziness, weakness, apprehension, confusion, palpitations, and sometimes trouble breathing. Coprine is found mainly in mushrooms of the genus Coprinus, although similar effects have been noted after ingestion of Clitocybe clavipes.
- Ibotenic acid: This organic acid is metabolized to muscimol. The effects of muscimol vary, but nausea and vomiting are common. Confusion, euphoria, or sleepiness are possible. Loss of muscular coordination, sweating, and chills are likely. Some people experience visual distortions, a feeling of strength, or delusions. Symptoms normally appear after 30 minutes to 2 hours and last for several hours. A. muscaria, the "Alice in Wonderland" mushroom, is known for the toxic/hallucinogenic properties caused by ibotenic acid, but A. pantherina and A. gemmata also contain the same compound. While normally self-limiting, fatalities have been associated with A. pantherina, and consumption of a large number of any of these mushrooms is likely to be dangerous.
- Psilocybin: This compound is converted into psilocin when ingested. Symptoms begin shortly after ingestion. The effects can include euphoria, visual and religious hallucinations, and heightened perception. However, some persons experience fear, agitation, confusion, and schizophrenialike symptoms. All symptoms generally pass after several hours. Some (though not all) members of the genus Psilocybe contain psilocybin, as do some Panaeolus, Copelandia, Conocybe, Gymnopilus, and others. Some of these mushrooms also contain baeocystin, which has effects similar to psilocin.
- Arabitol: A sugar alcohol, similar to mannitol, which causes no harm in most people but causes gastrointestinal irritation in some. It is found in small amounts in oyster mushrooms, and considerable amounts in Suillus species and Hygrophoropsis aurantiaca (the "false chanterelle").
Some mushrooms contain less toxic compounds and, therefore, are not severely poisonous. Poisonings by these mushrooms may respond well to treatment. However, certain types of mushrooms, such as the Amanitas, contain very potent toxins and are very poisonous; so even if symptoms are treated promptly mortality is high. With some toxins, death can occur in a week or a few days. Although a liver or kidney transplant may save some patients with complete organ failure, in many cases there are no organs available. Patients who are hospitalized and given aggressive support therapy almost immediately after ingestion of amanitin-containing mushrooms have a mortality rate of only 10%, whereas those admitted 60 or more hours after ingestion have a 50–90% mortality rate.
Cap is a convex round, then is extensive, ocher brown in color, covered with brown scales darker shades,
pleasant and mild aroma, grows in deciduous forests and parks.
Cap is convex then spread out, white with shades of brown and covered with scales, thick pulpy, foul smell, growing in the grass, on pastures, meadows.
Cap hemispherical convex, then flat white color with brown scales on the surface of the cap, growing in meadows, pastures and gardens.
Bubble is the first spherical bell, then flattened, white, yellowed fingers to touch, to grow in the summer and autumn, in parks, along roads, along the edge of woods, meadows and bushes.
Cap is a convex round, then spreading, gray with shades of brown and ocher tones, smells unpleasant, it grows
in deciduous forests, under shrubbery, in the parks.
Bubble is convex, then spread out, the white, cone surface is covered with shades of brown scales, intense smell of phenol or cartridges, grows in woods, parks, particularly under the acacia.
Cap is convex and hemispherical, then open and truncate , dark brown, with bright shades of, covered with dark
brown scales, unpleasant smell like ink, it grows on damp ground in woods and meadows.
Cap is convex then widespread,red or orange-red color,stem of of white color,has hanging ring,grows in deciduous and coniferous forests in summer and autumn,rare species.
Cap is convex then widespread,light brown with reddish shades,covered with warty white, stem of white base
is thickened tuberous, has hanging ring,grows in spruce forests in the summer.
Cap thick, fleshy, convex then widespread, white-brown or light brown with reddish shades of, stipe a robust, covered with a thick red grid, the basic colors yellow stipe, grows in the summer and autumn by beech and oak forests.
Cap tough, fleshy, convex, close to the stipe, Stipe thick, yellow under the cap, then goes to red, and in the thickest part of the blood red, unpleasant smell, taste sweet and insipid, it grows in the summer in deciduous forests.
Cap convex, then widespread, fleshy, yellow with red spots, the touch of blue, stipe paunchy, basic colors yellow, covered with a red grid, the touch of blue, rises in summer and autumn in the deciduous forests.